• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.3
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• pp.379-385
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• 2022

This study was conducted to evaluate the dietary supplementation of citrus byproduct (CBP) on the growth performance, feed utilization, and innate immune responses of juvenile olive flounder Paralichthys olivaceus under low water temperatures (11-15℃). Dietary L-ascorbyl-2-polyphosphate was replaced with graded CBP levels at 0 (Con), 25 (CBP25), 50 (CBP50), 75 (CBP75), and 100% (CBP100). Triplicate groups of juvenile olive flounder were handfed with one of the diets twice a day for 42 days. The growth performance and feed utilization of fish fed with diet containing levels of CBP75 or CBP100 increased significantly compared to those of fish with fed Con. Dietary CBP supplementation increased the protein efficiency ratio in fish. There was no significant differences in innate immune responses between groups, even though CBP supplementation tended to increase. These findings indicate that CBP could be used as a vitamin C source and improve the growth performance of juvenile olive flounder under low water temperatures.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.255-259
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• 1998

Sixteen Friesian Cows were allocated equally into 4 groups in a $4{\times}4$ Latin square design to evaluate the effects of utilizing bean by-products on the feed intake and milk production. Cows were fed on 4.5% of their body weight fresh alfalfa; the remainder of their requirements were covered by one of 4 experimental concentrate treatments: 1) commercial concentrate (CC), 2) 70% CC + 30% bean hulls (BH), 3) 70% CC + 30% Polished bean (PB) and 4) 70% CC+ 15% BH + 15% PB. Results showed that the inclusion of bean hulls at 30% improved (p<0.05) milk yield, 4% fat corrected milk yield, feed conversion ratio and fat percent of the milk over the other treatments. Feeding cows on a commercial concentrate plus 30% BH or 30% PB or 15% from each of BH and PB decreased the cost of feed per kg milk by 13.6, 2.5 and 1.3 %, respectively, lower than those fed on the commercial concentrate.

• Korean Journal of Poultry Science
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• v.22 no.2
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• pp.105-115
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• 1995

The balance of microbial populations in the gastrointestinal (GI) tract of all warm-blooded animals is critical to the maintenance of health and resistance to disease. The composition of the populations can be altered by diet and environment, making the host animal susceptible to disease, and reducing growth rate and feed efficiency. Some feed additives including antimicrobial agents, prohiotics or yucca extract have been used to promote growth and feed utilization. There is evidence that part of growth-promoting effect of those feed additives results from the suppression of microbial urease activity or ammonia production in the GI contents of animals. Over 200 microbial species have been known to produce urease and the product of urea hydrolysis, ammonia, is toxic to animals. Carefully tested probiotics or other urease-suppressing agents can be a possible alternative to antimicrobial agents including antibiotics as growth promotants used for animals feeds.

• KSBB Journal
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• v.14 no.4
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• pp.495-502
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• 1999

The optimization of fed-batch yeast fermentation process has been performed using genetic algorithm(GA). Three strategies were designed and applied to obtain the optimal feed rate profiles. Genes in the chromosome (input variables for optimization) included feed rates on fixed time intervals (strategy I), or swiching times $t_s1\;and\;t_s2$, and feed rates on singular arc (strategy II), or feed rates and the length of time interval (strategy III). Strategy III showed the best results for all initial conditions due to efficient utilization of genetic information. Simulation results using GA showed similar or better performance compared with previous results by variational caculus and singular control approach.

• Korean Journal of Poultry Science
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• v.33 no.3
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• pp.239-248
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• 2006

Improvements in understanding the effects of dietary fermentable carbohydrates and their interaction with supplemental feed enzymes and the feed manufacturing process may lead to reductions in volatile organic compound (VOC) emissions from poultry manure. Starch digestibility has been improved by replacing ground wheat or barley with whole wheat or barley, but there was no consistent effect of cereal species or feed form on the pH value of the gizzard contents. Pelleting results in improvements in feed conversion from 0 to 12%. Starch digestibility has been reported to account for up to 35 % of the improvement in available metabolic energy as a result of xylase supplementation. Factors which affect starch utilization and non-starch polysaccharide (NSP) absorption include the presence of anti-nutrient facto. (ANF) in grains, the nature of grain starch, NSP and the digestive capacity of animals. Improvements in feed production technology have been made in enzyme stabilization, allowing some dry enzyme products to be pelleted after conditioning at up to $87.69^{\circ}C$ and liquid enzymes to be stored in the feed mill for up to low months prior to use. The soluble NSP, arabinokylans and beta-glucans are partially degraded into smaller fragments by enzymes. With fragmentation, the water holding capacity is decreased, which leads to a reduction in digesta moisture, wet feces, and dirty eggs from hens fed diets containing viscosity-inducing ingredients.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1430-1438
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• 2019

Objective: This experiment was designed to determine the effects of coated cysteamine hydrochloride (CC) on muscle fiber characteristics, amino acid composition and transporters gene expression in the longissimus dorsi muscle (LDM) of finishing pigs. Methods: Two hundred and sixteen Duroc/Landrace/Yorkshire cross-bred male finishing pigs were fed with a corn-soybean basal diet supplemented with 0, 70, and 140 mg/kg cysteamine. Each group contained eight replicates of nine pigs per replicate. After 29 days, one pig was randomly selected from each replicate and slaughtered. Blood and LDM samples were collected and analyzed. Results: The results showed that supplemental dietary CC increased (p<0.05) the muscle fiber density. And CC supplementation also up-regulated (p<0.05) the expression of myosin heavy chain 1 (MyHC1) and MyHC2x mRNA levels, and down-regulated (p<0.05) MyHC2b expression in the LDM. Additionally, supplemental dietary CC reduced (p<0.05) the concentration of total cholesterol in the plasma and enhanced (p<0.05) the concentrations of essential amino acid and total amino acid in the LDM. The relative expression levels of chloramphenicol acetyltransferase 2, $b^{0,+}$ amino acid transporter, and $y^+$-L-type amino acid transporter 1 were upregulated (p<0.05) in the LDM when pigs were fed with the dietary CC of 70 mg/kg. Conclusion: Cysteamine supplementation could increase fiber density and distribution of fiber types. It also improved the deposition of protein in the LDM by up-regulated the expression of amino acid transporters.

• Journal of Mushroom
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• v.17 no.3
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• pp.85-92
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• 2019

Over a million tons of spent mushroom substrate (SMS) are generated as by-products of mushroom cultivation every year in Korea. Disposal of SMS by mushroom farmers is difficult, therefore, recycling solutions that do not harm the environment are necessary. SMS consists of mushroom mycelia and residues of fruiting bodies, containing a variety of bioactive substances, such as extracellular enzymes, antimicrobial compounds, and secondary metabolites. This paper reviews utility of SMS for bioremediation, controlling plant disease, and production of lignocellulytic enzymes, organic fertilizer, and animal feed.

• Korean Journal of Poultry Science
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• v.45 no.1
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• pp.1-15
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• 2018

Salmonella infections in livestock industry cause various problems such as worsening animal welfare and productivity, damaging consumer confidence in the food safety of animal products. Chicken meat and eggs are known as major source of pathogen causing human foodborne infections. Therefore food safety concerns have prompted the poultry producers and governments to introduce the strategy and regulation to control these pathogens. Salmonella can persist for long periods of time in a wide range of spaces including feed bin, feed processing facilities, poultry farm, slaughterhouse, processing plants, etc. For the effective and constant Salmonella control, combination of pre-harvest, harvest and post-harvest measures should be considered comprehensively. The control measures would be most effective at farm level where the contamination initiates. Transmission of pathogen from feed origin to the live poultry and finally to the products was proven already. To control bacteria in the feed ingredients and formula feed, thermal processing, irradiation or chemical treatment may be applied. Chemical treatments to inhibit Salmonella in the feed involve the use of products containing organic acids, formaldehyde, or a combination of such compounds. However, recontamination which might occur during storage and transport process and/or by other various factors should always be under control and eliminated. Feed additives used to control Salmonella in birds' gastrointestinal track can be of various types, including prebiotics, probiotics, organic acids and bacteriophages. Although their mode of action varies, they ultimately inhibit the colonization of Salmonella in the gut and improve the performance of birds. This review describes the strategies that could be adapted to the management of feedstuffs and the use of feed additives in pre-harvest stage to control Salmonella contamination in poultry farming.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.185-188
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• 2019

The production of traditional cool season grasses in temperate regions is becoming hampered during summer seasons due to water deficit. Thus, incorporating water use efficient warm season annual grasses are generally considered to fill the gap of summer season forage reduction that would offer considerable flexibility and adaptability to respond to forage demand. Teff (Eragrostis teff Zuccagni) Trotter) is, a C4 drought tolerant warm season annual grass primarily grown for grain production, recently gaining interest for forage production particularly during summer season. Previous reports have showed that teff is palatable and has comparable forage biomass and feed quality as compared to other warm season annual grasses which would make it an alternative forage. However, the available data are not comprehensive to explore the potential of teff as forage, hence further assessment of genotype variability and performance along with compatibility study of teff with forage production system of specific environment is key for future utilization.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1141-1149
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• 2014

The present study was conducted to investigate a supplemental effect of magnesium hydrogen phosphate (MHP, $MgHPO_4$) as an alternative phosphorus (P) source on growth and feed utilization of juvenile far eastern catfish (Silurus asotus) in comparison with three conventional P additives (monocalcium phosphate (MCP), dicalcium phosphate (DCP) and tricalcium phosphate [TCP]) as positive controls. A basal diet as a negative control was prepared without P supplementation and four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 11.3 g following 24 h fasting after three week adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 8 weeks. Fish fed MHP had weight gain (WG), protein efficiency ratio and specific growth rate comparable to those fed MCP. Fish fed MHP and MCP had feed efficiency (FE) significantly higher (p<0.05) than those fed DCP. Fish groups fed control and TCP showed the lower FE than the other groups which was significantly different (p<0.05) from those of fish fed the other diets. Survival rate was not significantly different (p>0.05) among treatments. Fish fed control had the lowest hematocrit, which was significantly different (p<0.05) from that of fish fed MHP. Fish fed MCP and MHP had plasma P higher (p<0.05) than fish fed the other diets. Relative efficiencies of MCP, DCP and TCP to MHP were found to be 100.5 and 101.3%, 92.0 and 91.6%, and 79.1 and 80.9% for WG and FE, respectively. P availability was determined to be 88.1%, 75.2%, 8.7%, and 90.9% for MCP, DCP, TCP, and MHP, respectively. Consequently, MHP recovered from wastewater stream showed that as an alternative P source its performance was comparative with MCP on growth and feed utilization of juvenile far eastern catfish.